Improve tests

test/livebook/runtime/erl_dist/runtime_server_test.exs

@@ -1,5 +1,5 @@
 defmodule Livebook.Runtime.ErlDist.RuntimeServerTest do
-  use ExUnit.Case, async: false
+  use ExUnit.Case, async: true
 
   alias Livebook.Runtime.ErlDist.{NodeManager, RuntimeServer}
 
@@ -51,13 +51,15 @@ defmodule Livebook.Runtime.ErlDist.RuntimeServerTest do
           assert_receive {:runtime_evaluation_response, :e2, _, %{evaluation_time_ms: _time_ms}}
         end)
 
-      assert stderr == ""
+      refute stderr =~ "redefining module Foo"
     end
 
     test "proxies evaluation stderr to evaluation stdout", %{pid: pid} do
-      RuntimeServer.evaluate_code(pid, ~s{IO.puts(:stderr, "error")}, {:c1, :e1}, [])
+      RuntimeServer.evaluate_code(pid, ~s{IO.puts(:stderr, "error to stdout")}, {:c1, :e1}, [])
 
-      assert_receive {:runtime_evaluation_output, :e1, {:stdout, "error\n"}}
+      assert_receive {:runtime_evaluation_output, :e1, {:stdout, output}}
+
+      assert output =~ "error to stdout\n"
     end
 
     @tag capture_log: true

test/livebook/runtime/evaluator_test.exs

@@ -57,12 +57,10 @@ defmodule Livebook.Runtime.EvaluatorTest do
       Evaluator.evaluate_code(evaluator, "x = 1", :code_1, [])
       assert_receive {:runtime_evaluation_response, :code_1, _, metadata()}
 
-      ignore_warnings(fn ->
       Evaluator.evaluate_code(evaluator, "x", :code_2, [])
 
       assert_receive {:runtime_evaluation_response, :code_2,
                       {:error, _kind, %CompileError{}, _stacktrace}, metadata()}
-      end)
     end
 
     test "given parent refs sees previous evaluation context", %{evaluator: evaluator} do
@@ -227,7 +225,6 @@ defmodule Livebook.Runtime.EvaluatorTest do
       Livebook.Runtime.EvaluatorTest.Stacktrace.Cat.meow()
       """
 
-      ignore_warnings(fn ->
       Evaluator.evaluate_code(evaluator, code, :code_1, [])
 
       expected_stacktrace = [
@@ -241,7 +238,6 @@ defmodule Livebook.Runtime.EvaluatorTest do
       assert_receive {:runtime_evaluation_response, :code_1,
                       {:error, _kind, _error, ^expected_stacktrace}, metadata()},
                      2_000
-      end)
     end
 
     test "in case of an error uses empty evaluation context as the resulting context",
@@ -1005,12 +1001,10 @@ defmodule Livebook.Runtime.EvaluatorTest do
 
       Evaluator.forget_evaluation(evaluator, :code_1)
 
-      ignore_warnings(fn ->
       Evaluator.evaluate_code(evaluator, "x", :code_2, [:code_1])
 
       assert_receive {:runtime_evaluation_response, :code_2,
                       {:error, _kind, %CompileError{}, _stacktrace}, metadata()}
-      end)
     end
 
     test "kills widgets that no evaluation points to", %{evaluator: evaluator} do
@@ -1091,13 +1085,6 @@ defmodule Livebook.Runtime.EvaluatorTest do
 
   # Helpers
 
-  # Some of the code passed to Evaluator above is expected
-  # to produce compilation warnings, so we ignore them.
-  defp ignore_warnings(fun) do
-    ExUnit.CaptureIO.capture_io(:stderr, fun)
-    :ok
-  end
-
   # Returns a code that spawns a widget process, registers
   # a pointer for it and adds monitoring, then returns widget
   # pid from the evaluation

test/livebook_web/live/app_live_test.exs

@@ -64,6 +64,7 @@ defmodule LivebookWeb.AppLiveTest do
                         sessions: [%{app_status: %{lifecycle: :deactivated}}, _, _]
                       }}
 
+      assert render(view) =~ ~p"/apps/#{slug}/#{session_id1}"
       refute render(view) =~ ~p"/apps/#{slug}/#{session_id3}"
 
       App.close(app_pid)